Ruby on Rails: read user submited .txt file into variable - ruby-on-rails

Question

I'm building a ruby on rails app that lets the user pick a file from their hard drive, and then writes specific lines from the text file into a database. I've built the form, but now I don't know how to get the content of the file into a variable, format it and then write it into the database.
I have a database table named drafts with colums set_1, set_2, set_3. I want to write line 13(from the text file) into set_1, line 165 into set_2 and line 317 into set_3. I also want to format the lines before writing them. In the file they look like this ------ FRF ------ and I only want FRF.
I've spent a lot of time searching stackoverflow and rubyonrails guides but have a hard time figuring this out. I'm very new to ruby and rails in general, so any help is appreciated.
Here's my controller (drafts_controller.rb):
class DraftsController < ApplicationController
def new
#page_title = "Upload MTGO Draft"
#draft = Draft.new
end
def create
#draft = Draft.new(draft_params)
if #draft.save
flash[:notice] = "Draft Saved!"
redirect_to drafts_show_path
else
render "new"
end
end
def index
#page_title = "MTGO Draft"
end
def show
#page_title = "MTGO Draft Replayer"
end
def search
#page_title = "Search MTGO Draft"
end
def destroy
end
def draft_params
params.require(:draft).permit(:name, :set_1, :set_2, :set3, :file_setter)
end
end
and my view: (new.html.erb):
<%= form_for #draft, :multipart => true do |f| %>
<div class="form-group">
Draft Log: <%= f.file_field :file_setter %>
<%= f.submit 'Save' %>
</div>
<% end %>
here's the model (draft.rb)
class Draft < ActiveRecord::Base
def file_setter=(file)
path = file.tempfile.to_path.to_s
lines = File.read(path).split("\r\n")
self.set_1 = lines[12]
self.set_2 = lines[164]
self.set_3 = lines[316]
end
attr_accessor :file_setter
end
If you need more info or want to get into the whole app more he's a gitHub repository.
Thanks for the help.
Here's the log excerp:
Started POST "/drafts" for 127.0.0.1 at 2015-04-10 10:52:57 +0200
Processing by DraftsController#create as HTML
Parameters: {"utf8"=>"✓", "authenticity_token"=>"8IjtOXuXm3fswWTslDTq5ijjo0dpCWHlu9X7UFb5prvawrZfkLC46v7PbqTgrSrvukLxAAoBIBftsGqiXv79JA==", "draft"=>{"file_setter"=>#<ActionDispatch::Http::UploadedFile:0x00000005ee4a08 #tempfile=#<Tempfile:/tmp/RackMultipart20150410-3067-1fssm13>, #original_filename="1", #content_type="application/octet-stream", #headers="Content-Disposition: form-data; name=\"draft[file_setter]\"; filename=\"1\"\r\nContent-Type: application/octet-stream\r\n">}, "commit"=>"Save"}
[1m[36m (0.2ms)[0m [1mBEGIN[0m
[1m[35mSQL (1.8ms)[0m INSERT INTO `drafts` (`created_at`, `updated_at`) VALUES ('2015-04-10 08:52:57', '2015-04-10 08:52:57')
[1m[36m (41.6ms)[0m [1mCOMMIT[0m
Redirected to http://localhost:3000/drafts/show
Completed 302 Found in 57ms (ActiveRecord: 43.6ms)

Answer 1

Add this method to your model:
def file_setter=(file)
path = file.tempfile.to_path.to_s
lines = File.read(path).split("\r\n")
self.set_1 = lines[12]
self.set_2 = lines[164]
self.set_3 = lines[316]
end
In your form change the file_field value from :file to :file_setter like this:
<%= form_for #draft, :multipart => true do |f| %>
<div class="form-group">
Draft Log: <%= f.file_field :file_setter %>
</div>
<% end %>
// Its very important that you add :multipart => true to the form_for method. Otherwise file uploads wont work.
// Also add this to your model:
attr_accessor :file_setter
// In your controller you have to change this:
def draft_params
params.require(:draft).permit(:name, :set_1, :set_2, :set3)
end
To this:
def draft_params
params.require(:draft).permit(:name, :set_1, :set_2, :set3, :file_setter)
end